Glock strongly discourages the use of non-jacketed bullet in its products. As pointed out by Justin, Glocks have a tendency for severe leading of the barrels which can lead to dangerous over pressure conditions. Aftermarket barrels are available in the $200 range that will allow for the use of non-jacketed bullets. These barrels usually have fully supported chambers which also decrease the likelihood of a case rupture.
Get a lonewolf SS barrel and your in bussiness. it also has a tighter tolerance and they are accurate and they just drop in with no gun smithing. $107.00 also cures the headspacing problem. the stainless barrel kind of looks good on it. To me anyway. My stock barrel is in reserve now. Jack